2 October 2013: CAMBRIDGE, UK AND SURESNES, FRANCE – XENTION LTD ("Xention"), the Cambridge-based biopharmaceutical company specialising in the discovery and development of ion channel-modulating drugs for atrial fibrillation, and SERVIER, the leading independent French pharmaceutical company ("Servier") announced today that they had entered into a multi-year agreement for the development and commercialisation of XEN-D0103, a selective Kv1.5 modulator discovered and developed by Xention for the treatment of atrial fibrillation ("AF").

Under the terms of the agreement, Servier has received an option to acquire certain intellectual property rights and to further develop and commercialise XEN-D0103 in all territories except the USA and Japan. All rights in the USA and Japan will be retained by Xention.

During the option period, the parties will undertake a joint programme of clinical development of XEN-D0103 undertaking two phase 2 clinical studies aimed at demonstrating the efficacy of XEN-D0103 in reducing AF burden in paroxysmal AF. In addition to an upfront fee, Servier will pay an option fee as well as a series of milestones totalling €120 million. When Servier exercises its option, it will be responsible for the further clinical development and commercialisation of XEN-D0103 within its territories.

XEN-D0103 is a potent and selective blocker of Kv1.5, a potassium channel expressed in the atria, which represents an exciting new target for atrial fibrillation. Xention's unique ion channel and cardiovascular development capabilities were critical for the discovery and development of this innovative compound, which has been shown to be safe and well tolerated in phase 1 clinical development.

Tim Brears, CEO of Xention said: "Servier has significant expertise in the development and commercialisation of cardiovascular drugs and represents an excellent partner for Xention. We are delighted to be working with Servier on this exciting project."

Dr Isabelle Tupinon Mathieu, Vice President Research and Development for Cardiovascular and Metabolism Therapeutic Innovation Poles at Servier said: "We look forward to be working on the further development of XEN-D0103, which represents an innovative new approach to atrial fibrillation. This compound is unique in its potency and specificity for Kv1.5, a key atrial selective cardiac ion channel."

"Participating in the development of this innovative drug in atrial fibrillation further expands our portfolio of drugs aimed at treating various cardiac diseases and at offering patients with this very debilitating disease a new treatment opportunity" said Dr Jean Philippe Seta, CEO of Servier.

For further information, please contact:

Tim Brears 01223 493 900

Xention Limited tim.brears@xention.com

Tristan Jervis 020 7203 6740

Defacto t.jervis@defacto.com

About Xention Ltd:

Xention is a leader in the discovery and development of ion channel-modulating drugs. The Company is developing a pipeline of innovative products for the treatment of atrial fibrillation, an indication for which there is high unmet medical need, by targeting key ion channels. Xention uses an innovative approach to discover and design potent and selective small-molecule drugs and has collaborations with several companies. In atrial fibrillation, the company is developing modulators of Kv1.5 and IKACh, both recognised as novel, highly exciting new targets for the disease. Xention is actively developing these selective modulators of AF target, including IKACh. For further information, please see http://www.xention.com.

About Servier:

"From the very beginnings of the company we have reinvested the totality of our profits in research". Dr Jacques Servier

Servier is the leading independent French pharmaceutical company, established in 1954 by its founder, Jacques Servier, M.D., Pharm.D. The group is established in 140 countries and 92% of Servier products are prescribed out of France. Sales turnover in 2012 rose to 3.9 billion euros. Almost 25% of Servier's turnover is invested in Research and Development. The Servier Group counts 19 International Centers of Therapeutic Research, and its principal therapeutic research orientations are cardiovascular diseases, diabetes, neuropsychiatric disorders, cancer and rheumatology.
More information is available at: www.servier.com.